In a portable radio communication device such as a cellular phone, it is recently a considerable problem to avoid interference of an electromagnetic noise emitted from each embedded electronic component to a radio system. As a measure to suppress such a noise, a method has been conventionally general in which a circuit that includes a source is enclosed with a metal sheet (sheet metal shield). However, this method has a problem of causing increase in size and height of a device.
Thus, it is studied to apply a shielding measure to the electronic component itself being the source, and a package (hereinafter, referred to as a shield semiconductor package) in which a shield layer is provided on a surface of a resin-shielded semiconductor package by plating is developed. In such a semiconductor package, a component itself can be shielded and, in addition, a shield layer can be formed to be very thin, which leads to further decrease in size and thickness of the device.
However, on the other hand, there is a possibility that a shield performance is impaired at a time that product information is marked by a laser, due to penetration through the shield layer. Further, if a depth of marking is decreased for the purpose of preventing such penetration, visibility is deteriorated.